Orthodontic treatment in the presence of aggressive periodontitis

ABSTRACT Introduction: Aggressive periodontitis causes periodontal destruction, with loss of supporting alveolar bone. The common symptom is rapid attachment loss in the first molar and incisor area, in young adults. Objective: The aim of this study was to discuss the challenges, implications and the impact of orthodontic treatment in patients affected by severe periodontal problems, specifically aggressive periodontitis. Discussion: In addition to other bacteria, the main pathogen involved in aggressive periodontitis is the Aggregatibacter actinomycetemcomitans. However, the susceptibility to the disease differs among individuals, being immune deficiencies the main reason for this variability. Many orthodontists are not comfortable about performing treatments on individuals with aggressive periodontitis. Conclusion: Orthodontic treatment is feasible in young patients with severe and localized aggressive periodontitis, as long as the limitations imposed by the disease are respected. An interdisciplinary approach is required, with frequent periodontal follow-up before, during and after orthodontic treatment, allowing the correction of dental positions without aggravating bone loss.


INTRODUCTION
Aggressive periodontitis (AgP) is a type of periodontitis with early onset and rapid progression, causing periodontal destruction, with loss of supporting alveolar bone. 1 This disease causes localized breakdown of the periodontal attachment in specific regions of the dental arch early in life. The common symptom is rapid attachment loss in the first molar and incisor area. 2 It mostly affects young adults in the age range of 15-35 years, which is the common age group for patients' seeking orthodontic treatment. Therefore, education regarding periodontitis, especially AgP, is essential among orthodontists and general dentists. 3 The Aggregatibacter actinomycetemcomitans (previously known as Actinobacillus actinomycetemcomitans) is found in high frequency in microbial deposits on the affected teeth, and is considered, besides other bacteria, the major pathogen to be involved in AgP. Even though, the susceptibility of the disease differs among individuals, being immune defects the reason for this variability. 1 The prevalence of AgP varies considerably between studies.
A systematic review found a relatively high prevalence in Africa and South America, compared with Europe, Asia and North America. However, the authors highlighted the weakness of the definition of this form of periodontal disease, and suggested that studies with less heterogeneity are needed. 4 These findings show that AgP is a significant health problem in certain populations. 5 Different forms of periodontal disease have a distinct impact on the quality of life. Patients with a diagnosis of generalized forms of chronic or aggressive periodontitis showed poorer quality of life than those diagnosed with localized AgP, which was shown mainly by significant differences in the physical pain and psychological discomfort. 6 Many orthodontists are not comfortable in performing treatments in subjects with AgP. 7 Otherwise, orthodontic treatment is feasible in young patients with severe and localized AgP, as orthodontic tooth movements are possible independent of the attachment level, and without worsening it. 8 When treating periodontal patients, orthodontists must consider an interdisciplinary approach, since interaction with the periodontist and a proper chronology of events are important factors for success. 9 These cases should be planned individually, considering bone losses suffered by each patient. Respecting some limitations, it is possible to improve the level of bone insertion and facilitate oral hygiene through the orthodontic treatment of adult patients with little bone support. 10 It may also help to prevent inflammation and the recurrence of periodontal disease. 2 Thus, the aim of this study is to discuss the challenges of orthodontic treatment in patients with severe periodontal problems.
Additionally, it aims at reporting the clinical case of a young woman presenting AgP, with several dental and orthodontic problems related to it.

DIAGNOSIS
Female patient, aged 16 years and 3 months, was referred by a periodontist for orthodontic treatment. She reported, in addition to the gingival problem, chief complaints about "teeth shifting forward", "teeth opening spaces" and "inverted bite on the back". She presented good general health condition, but with a family history of periodontal disease.
The frontal extraoral clinical examination revealed a slight deviation of the chin to the right, and an increased lower anterior facial height. The profile was convex, with a small nose, prominent chin, and protruded lips. The intraoral examination showed an Angle Class I with right anterior (#13) and posterior crossbite, a steep Curve of Spee, abnormal maxillary and mandibular arch forms, and deviated dental midlines    (Fig 3).
A functional analysis showed that lip sealing was not completely passive, due to upper incisors' projection. Also, maxillary incisors showed a decreased exposure at rest, less than the ideal for a young woman. The enlarged shape of the mandibular arch indicated a large tongue with a low rest posture, but without the habit of projection. There was also a lack of adequate guides in the excursive mandibular movements, resulting from crossbite and other occlusal problems.

TREATMENT OBJECTIVES
The treatment objectives of the present clinical case were initially based on preventing disease progression through frequent periodontal follow-up before, during and after orthodontic treatment, allowing the correction of dental positions without aggravating bone loss.
Regarding facial esthetics, the aim was to obtain facial symmetry, maintain the profile and vertical dimension, and increase the exposure of the maxillary incisors at smile. In dental aspects, the objective was to maintain Angle Class I, correct crossbite, arch form and level the curve of Spee; to obtain coincident midlines and a correct overjet, promoting space in the maxillary arch to reduce incisor projection and prepare the space for rehabilitation of the maxillary right central incisor (#11). Finally, to establish good intercuspation and adequate functional occlusal guides.

TREATMENT OPTIONS
The considered treatment options were to perform posterior crossbite correction through conventional rapid maxillary expansion (RME), since the patient was 16 years old, or opt for a surgically-assisted maxillary expansion (SARME). At the time of treatment, the modality of miniscrew-assisted rapid palatal expansion (MARPE) was not yet established in the literature.
It was then decided to try a RME with a conventional tooth-borne expander, without the aid of surgery, despite the borderline age.

TREATMENT PROGRESS
Initially, third molar extraction surgery was performed. Then, a Hyrax expander was installed, with bands on the maxillary first molars (#16 and #26) and first premolars (#14 and #24), and distally extended to contour the palatal surface of the maxillary second molars (#17 and #27) to increase anchorage. The screw was activated twice a day for 14 days, totaling 7mm (Fig 4).
It was observed more dental than skeletal expansion, probably influenced by patient's age and periodontal support, so the retention period for this procedure was reduced to only three Subsequently, after correcting the crossbite of the maxillary right canine (#13) and removing the expander, the same type of appliance was mounted on the maxillary arch, but not including the incisors, to avoid its projection. Alignment and leveling was started with 0.015-in Twist-flex and 0.016-in NiTi archwires. Using spaces generated by the maxillary expansion, the distalization of the #13 was started with an elastic chain (Fig 6).  In the maxillary arch, a 0.019 x 0.026-in stainless steel archwire was inserted, and interproximal reduction was done on maxillary left (#21) and right (#11 provisional crown) central incisors, determining adequate space for rehabilitation. At different surgical times, bone graft surgery was performed in the atrophic region (Fig 7), followed by installation of an osseointegrated implant and implant-supported provisional crown of the #11 (Fig 8).  In functional aspects, there was improvement in lip sealing at rest after correction of the maxillary incisors, in addition to obtaining correct excursive guides in laterality and protrusion.
The panoramic radiograph (Fig 10) and complete periapical examination  Cephalometric radiograph and cephalometric tracings (Fig 12 and Table 1), as well as cephalometric superimpositions (Fig 13) show that the anteroposterior and vertical skeletal aspect was maintained, with a small reduction in the mandibular plane, without clockwise rotation. There was verticalization of the maxillary incisors and slight projection of the mandibular incisors, with slight molar mesialization in both arches.

DISCUSSION
Aggressive periodontitis (AgP) was formerly called juvenile periodontitis or early-onset periodontitis. 2 Since its introduction in 1999, the term aggressive periodontitis has been the topic of many investigations, but with significant heterogeneity in the understanding and use of this term. 11 A new periodontitis classification scheme has been adopted in 2018, in which forms of the disease previously recognized as "chronic" or "aggressive" are grouped under a single category ("periodontitis") and are further characterized based on a multi-dimensional staging and grading system. 12 On the other side, recent studies 3,4,6,11,13 have continued to adopt the term aggressive periodontitis describing research samples and case reports involving orthodontic-periodontal treatments.
The general approach to determining the orthodontic diagno- orthodontic treatment had no significant impact on periodontal outcomes in non-periodontitis and in stable periodontitis treated patients. 16 Carvalho et al. 13 showed that orthodontic treatment can be performed in AgP patients, and observed that orthodontic movement of the teeth resulted not only in stability of the periodontal tissues, but also in a slight but significant improvement in periodontal conditions. They also concluded that AgP The treatment of pathologic extruded and flared anterior teeth is a main concern in AgP patients, 18 and early diagnosis and treatment are essential for successful long-term prognosis. 17 Combining periodontal therapy, orthodontic treatment, and prosthodontics can greatly improve function and the esthetic result. 7 It is also important to highlight that there are unique aspects in the orthodontic retention in these cases. 10 As The prognosis could be considered uncertain, especially for some regions that already had more severe bone loss, with the risk of worsening the problem; as well as for long-term stability, due to the unpredictability of the patient's periodontal health, which would require constant periodontal monitoring.
Despite the great periodontal limitations of the present case, it was believed that leaving this patient without any orthodontic treatment could be more harmful in the long term than taking the risk of aggravating the periodontal condition of some regions, for example teeth #36 and #46. Post-treatment radiographs suggest that there was no worsening of the general and localized periodontal aspect, but limitations can be observed in obtaining correct root parallelism, due to bone deficiency. Shen et al. 19 showed that, after active periodontal treatment, orthodontic treatment in AgP patients had not aggravated inflammation and alveolar bone resorption, but root resorption occurred in two-thirds of incisors, approximately. Otherwise, we did not observe significant root resorption in the present clinical case.
It is expected that the patient's new occlusal, clinical and aesthetic condition will contribute to the maintenance of better oral health. Unfortunately, it was not possible to recall the present patient for post-retention follow-up records. Zafiropoulos et al. 20

CONCLUSIONS
Orthodontic treatment with adequate occlusal, functional and esthetic results can be performed in young adults presenting aggressive periodontitis. An interdisciplinary approach is required, with frequent periodontal follow-up before, during and after orthodontic treatment, allowing the correction of dental positions without aggravating bone loss.